You might be paying more than you need to for wireless or broadband service.

Because most users don't know how much data they use a month, companies can sell you expensive plans that you don't need. People often buy more data than they need because they are worried about going over and getting charged fees.

The Government Accountability Office put together a report that looks at how much people pay for their wireless and broadband services compared to how much data they actually use.

“Consumers may not be fully benefiting from lower-cost options under (usage-based pricing)” plans, the GAO said in its report. One wireless Internet provider told government investigators that only a small percentage of customers use 500 megabytes or lower plans even though the average wireless customer in the U.S. uses just 465MB of data monthly, according to a Sandvine survey.

There are tools out there to help you.

Some providers like Verizon, Sprint and AT&T offer data calculators on their websites to help you come up with your estimated usage. They look at the type of things you are downloading and what gadget you're using to see how much data you'll probably download each month. Verizon will also send you periodic text messages if you want to let you know when you're getting close to your data limit on your phone.